Deep-sea electric telephone cable

May 7, 1935.

E. SICHTERMANN 2,000,355

DEEP SEA ELECTRIC TELEPHONE CABLE

Filed April 15, 1933

<img file="US2000355A_D0001.tif" />

<img file="US2000355A_D0002.tif" />

<img file="US2000355A_D0003.tif" />

<img file="US2000355A_D0004.tif" />

<img file="US2000355A_D0005.tif" />

<img file="US2000355A_D0006.tif" />

Jn ven tor;

<img file="US2000355A_D0007.tif" />

Patented May 7, 1935

2,000,355

UNITED STATES PATENT OFFICE

2,000,355

DEEP-SEA ELECTRIC TELEPHONE CABLE

Eugen Sichtermann, Rodenkirchen, near Cologne, Germany

Application April 15,1933, Serial No. 666,861 3 Claims. (Cl. 173—265)

My invention relates to deep-sea electric telephone cables which are made of a plurality of strands assembled to a solid rope-like body, the said strands having on their joint surfaces restrictions which form channels holding the conductors and the papers for the insulation of the said conductors and including moreover sufficient free space for the necessary insulating air. My Invention relates more particularly to deep-sea electric telephone cables of the class referred to in which the said strands consist of rubber or gutta percha or of any other Insulating material offering very great resistance to a reduction in volume by pressure on alksides.. The primary object of my invention consists' in augmenting the flexibility and in decreasing the weight of such cables by securing the same against the bad influence of one-sided pressure occuring especially during the laying of the cables, the said bad influence consisting in contractions of the channels and in disturbances of the air-insulation of the conductors arising in consequence of said contractions. Other objects of my invention will be apparent from the following specification of preferred embodiments of my invention as Illustrated in the accompanying drawing in which

Fig. 1 is a cross-section of a cable consisting of six strands of rubber having joint surfaces provided with interlocking teeth or projections, on which joint surfaces the channels for the conductors are provided.

Figs. 2 and 3 are cross-sections of cables similar with the embodiment according to Fig. 1 but consisting each only of four strands of rubber.

Fig. 4 is a cross-section of a cable in which the channels for the conductors are formed between four strands of rubber, each of which strands is T-shaped in cross-section.

Fig. 5 is a cross-section of a cable consisting of three strands of rubber, two of which are Tshaped in cross-section, and one of which is double T-shaped in cross-section to form the channels for the conductors between them.

According to Fig. 1 the cable consists of six strands 5 of rubber or gutta percha offering great resistance to a reduction in volume by pressure on all sides. On the joint surfaces of the said strands niches or groove-like recesses 6 are provided which through adjacency to the other joint surfaces form the channels for the conductors 7 which in this case consist each of a single wire wrapped with paper. The said paper-wrapped conductors are surrounded by air-spaces a reduction of which under the influence of the water pressure is avoided by the strands of rubber or gutta percha offering great resistance to a reduction in volume by presure on all sides. The cable is encompassed by a lead sheathing 8 to prevent a soaking of water into the channels. This arrangement offers the possibility of embedding into the interior of the 5 rubber strands naked wires 9 which serve for telegraphing. A joggle joining between adjacent strands offers security against a relative displacement of one strand to another under the influence of one-sided pressure. 10

Figs. 2 and 3 show cables each of which is made of four strands 10. Each strand is provided on the one side with two steps 11, 12 and on the other side with a niche or groove-like recess, so that channels 13 are formed into which the con- 15 ductors 14 are loosely embedded. This cable is also encompassed by a lead sheathing 15. According to Fig. 2 the four strands are adjoining in the centre of the cable, but according to Fig. 3 only two oppositely arranged strands are adjoin- 20 ing in the centre of the cable, whereas the two other strands lean upon the first-mentioned two strands.

Fig. 4 shows an especially simple embodiment of my invention. The cable is made of four 25 strands of T-shaped cross-section. The oppositely arranged strands 16, 16 and 17, 17 are of the same cross-section. Between the said strands channels 18 of square cross-section are formed into which channels the conductors 21 30 are embedded. A joggle joining between adjacent strands may in this case be dispensed with, as a one-sided pressure in the direction of the arrow 22 from the strand 16 towards the strand 17 is taken up by the surfaces 19, 20, and a one- 35 sided pressure in the direction of the arrow 23 is taken up by the surfaces 24, 25, so that also in this case a displacement of one strand to another is avoided. The cable is encompassed by a lead sheathing 26. 40

Fig. 5 shows another simple embodiment of my invention. The cable is made of three strands two of which strands 27, 27 being oppositely arranged are of the same T-shaped cross-section. The third strand 28 is of a double T-shaped cross- 45 section. By this arrangement the assembling of the strands is further simplified and the price of the cable further reduced. The conductors may consist of single wires or may consist each of two or of four wires as shown in Fig. 5. For the 50 purpose of securing the conductors against moisture soaking in at leakiness of the lead sheathing 30, the paper-wrapped conductors are preferably encased in lead tubes 31. A crushing of the thin lead tubes during the assembling of the ⁶⁵

2,000,385 strands may be obviated by previously enveloping the conductors by hoses of rubber or gutta percha or by wrapping the said conductors up with small hollow ropes 32 of vulcanized rubber or gutta percha before the lead tubes are pressed over.

In the described embodiments the strands of which the cable is made and the channels for the conductors are arranged in such a way that through a one-sided pressure on the strands no contraction of the channels and in consequence thereof no disturbance of the air-insulation of the conductors can take place.